Process for the preparation of 13beta-n-propyl-delta4-gonene-17beta-ol-3-one and the intermediates in the preparation thereof



United States Patent 3074 978 PROCESS FGR THE 9 PREIARATKQN OF 135-11- PRfliYL-A -GONENE=17B=OL-3-ONE AND THE INTERMEDIATES IN THE PREPARATION wherein R is an alkyl radical having 1 to 18 carbon atoms and Acis the acyl radical of an organic carboxylic acid having 1 to 18 carbon atoms.

The oarboxylic acid esters of the 13fl-alkyl-A -gonene- THEREGF B 5 17B-ol-3-ones are more fully described in the copending, Gerard Noisy-165% and Rfibelft commonly assigned US. application Serial No. 96,062 court, Villiers-le-Bel (Seine and Oise), France, assignors fil d January 19 1961 h 13 ,1k 1 radical is an alkyl ia gg France a 0f radical having 1 to 18 carbon atoms. The carboxylic acids having 1 to 18 carbon atoms may be alkanoic or g ggg gfighg'ggg ighfi fiihgi jg i i 1%? 10 alkenoic acids, cycloalkyl alkanoic acids, aryl alkanoic 5 (CL acids or aryl carboxylic acids as set forth in said copending application.

The invention relates to a novel method for the saponi- The carboxylic ,acid esters of the 13 fidalkyb A4 gonene fication of carboxylic acid esters -of 13;8- alk yl-A -gonenemay be prepared according to the process 17 8-ol-3-ones wherein the carboxylic acid is an organlc disclosed in United States Patent application Serial No. W and having 1 to atoms The 96,062 and is illustrated by the steps comprising reacting tron also relates to novel intermediates formed in the an anyl halide with 6 methoxy 3AdihYdmnaPhthYlQ,1) P i direct saPomficauon isoxazole followed by hydrogenation to form 2-cyano-2-nsaid esters is particularly diflicult and gives only mediocre PYOPYL6 methoxy tetralone 1, reacting the latter with 20 methyl succinate to form 5-methoxy-13B-n-propyl-l5- It IS an ob ect of the invention to provide a novel procmathoxycarbony1 A5,q,9,14 des A gonat6traene 17 one I? ess for the sapomfication of carboxylic acid esters of 1318- acting the latter with an alkali metal borohydride to form alkylfA l j m 111511 welds 5 methoxy-13fi-n-propyl-l5-carboxy-A -des A-gona- It lanother object of t .wentlon 9 tetraene l7B-ol, heating the latter under acid conditions to term ediates for; the saponification of carboxyhc acid esters form 5 methoXy 13B n pmpy1 A5,q,9,14 des A gonatetmene of Q and Pamculaxly: 175-01, reducing the latter to form 5-methoxy-l3fi-n-pro- The lJEIIZOIC 361d ester *P "PY pyl-A -des-A-gonatriene-l7fl-ol, reacting the latter with flsodium in ammonia to form 13fl-n-propy1-A -des A-gofl -p py -g -3,17fi-di01. nene-li'B-ol-S-one, esterifying the latter with benzoic acid These and other objects and advantages of the invention to form l3fl-n-propyl-17fi-benzoyloxy-A -des A-gonene-S- will become obvious from the following detailed descripone, reacting the latter with pyrrolidine to form 5-pyrr1 11, roliidyl-13,B-n-propy]l-1zfl-benzoylgoxyingfiliig gdes \Aigfili- The process of the invention comprises reducing a carna iene, reacting e atter wit a o u-teneo boxylic acid ester of 13B-alkyl-A -gonene47,8-ol-3-one form 3-halo-l3p-npropyl-l7/3-benzoyloxy-4,5-seco A wherein the carboxylic acid is an organic carboxylic acid gonadiene-S-one, hydrolyzing the latter to form 13,8-nhaving 1 to 18 carbon atoms and the alkyl group has 1 to propyl-l7B-benzoyloxy-4,5-seco-A -gonene-3,S-dione, re- 18 carbon atoms with an alkali metal borohydride to form ducing the latte; t5) form 13fl-n-propgfi-lZfi-benzogloxyf,5- a carboxylic acid ester of 13fi-alkyl-A -gonene-3,175-diol, seco-gonane3, ione, con ensing e atter to orm 3,8- reacting the latter under alkaline conditions to form 13(3- n-propyl-l7(3-bcnzoyloxy-M-gonene-3-one and recovering alkyl-A -gonene-3,17fi-diol, selectively oxidizing the allylic 40 the latter. hydroxy group of the latter to form 13B-alkylA -gonene- I8 ltihe following11 example hthere are described several 17 -01-3-0ne and recovering the latter, em 0 iments IO ustrate t 6 invention. However, it

[2 preferred mode of the process of the invention comwould be understood that the invention is not intended to prises reacting the carboxylic acid ester of the 13 fi-alkylbe limited to the Specific embodiments. A -gonene-l7fl-ol-3-one with sodium borohydride to form EXAMPLE the carboxylic acid ester of l3f3-alkyl-A -gonene-3,175- diol, reacting the latter with an alkaline base such as an 1 7 v f the BenZOate f fi' -p p -g alkali metal hydroxide in a lower alkanol such as meth- 1 9411.410? 5- -1 opyl'testoster anol or ethanol to form 13,8-alkl-A -gonene-3,17B-diol, Step A: 0.5 gm. of the benzoate of l35-n-propyl-A oxidizing the latter with manganese dioxide to form 13 3- gonene-17fl-ol-3-one, obtained according to the United alkyl-N-gonene-l7,8-ol-3-one and recovering the latter. States Patent application Serial No. 96,062, filed January The reaction is illustrated in Table I. 19, 1961 was introduced into 10 cc. of methanol. 0.125

TABLE I R 0A R OAc R 011 c p O: HO NW HO gm. of sodium borohydride was added while cooling and the reaction mixture was agitated overnight to form a mixture containing the 17fi-benzoateof 13fl-n-propyl-A V gonene-3, 17 fl-diol.

a Step B: To the mixture 2.5 cc. of a 10% solution of potassium hydroxide in methanol were added and the mixture was heated to reflux for a period of four hours. The mixture was concentrated to a small volume and poured into iced water. The precipitated product was vacuum filtered, washed with water, dried and 393 mg. of raw 135- n-propyl-A -gonene-3,17fl-diol were obtained.

This product is not described in theliterature.

Step C: This last compound was dissolved in 80 cc. of dichlorethane. 2 gm. of-manganese dioxide were added andthe mixture was agitated at room temperature for a period of two hours. Theexcess manganese dioxide was and a specific rotation [a] =+64 (c.=O .5% in methanol). Ultraviolet spectra (ethanol) t'y at 240-241 m 6:16,)0.

Various modifications of the process may be made withv out departing from the spirit or scope ,of the invention and it is to be understood that the invention is to be limited only as defined in the appended claims. We claim:

1. A process for the preparation of 13fi-n-propyl-A d gonene-l7eol-3-one which comprises reducing a carboxylic acid ester of 135-n-propyl-A -gonene l7,8-01-3-one wherein the carboxylic acid is an organic carboxylic acid having 1 to 18 carbon atoms selected from the group consisting of alkanoic acids, alkenoic acids, cycloalkyl alkanoic acids, phenyl carboxylic acids and phenyl alkanoic acids with an alkali metal borohydride to form the corresponding 17-carboxylic acid ester of l'a'fi-n-propyhM- gonene-3,17B-diol, reacting the latter under alkaline conditions to form 13fl-n-propyl-M-gonene6,lTfi-diol, oxidizing the latter with manganese dioxide to form 1313mpropyl-A -gonene-l7,8-01-3-one and recovering the latter.

2. The process of claim 1 wherein the alkali metal borohydride is sodium borohydride.

3. A process for the preparation of 13=;3-npropy1A gonene-l7/3-ol-3-one which comprises reducing the henzoic acid ester of 1Elfi-n-propyl-M-gonene-l7f3-ol-3-one with sodium borohydride to form the benzoic acid ester References Qited in the file of this patent UNITED STATES PATENTS Wettstein et al Dec. 12, 1961 Counsell Dec. 26, 1961 

1. A PROCESS FOR THE PPREPARATION OF 13B-N-PROPYL-$4GONENE-17B-OL-3-ONE WHICH COMPRISES REDUCING A CARBOXYLIC ACID ESTER OF 13B-N-PROPYL$-4-GONENE-17B-OL-3-ONE W4WHEREIN THE CARBOXYLIC ACID IS AN ORGANIC CARBOXYLIC ACID HAVING 1 TO 18 CARBON ATOMS SELECTED FROM THE GROUP CONSISTING OF ALKANOIC ACIDS, ALLKENOIC ACIDS, CYLOAKLYL ALKANOIC ACIDS, PHENYL CARBOXYLIC ACIDS AND PHENYL ALKANOIC ACIDS WITH AN ALKALI METAL BOROHYDRIDE TO FORM THE CORRESPONDING 17-CARBOXYLIC ACID ESTER OF 13B-N-PROPYL$4GONENE-3, 17B-DIOL, EACTING THE LATTER UNDER ALKALINE CONTIONS TO FORM 13B-N-PROPYL$4-GONENE-3, 17B-DOIL, OXIDIZING THE LATTER WITH MANGANESE DIOXIDE TO FORM 13B-NPROPYL-$4-GONENE-17B-OL-3-ONE AND RECOVERING THE LATTER. 